This application claims the priority of a German patent application filed Jul. 14, 1998 bearing application no, 19831393.4.
1. Field of the Invention
The present invention concerns a door closer.
2. Description of Related Art
This type of door closer is known, for example, from DE 9319541 U1 that originated with the inventor. In that publication a door closer is described which exhibits a resisting spring and an hydraulic damper/attenuation element. The resisting spring acts directly on the damper piston and together with it operates in a common housing. The closer shaft is provided with a pinion that enmeshes with internal dentition in the damper piston.
In practice, two problems emerge from this type of construction. On the one hand, the thickness of the door closer in the radial direction of the closer shaft is relatively large, since the damper piston surrounds the closer shaft. On the other hand the resisting spring is situated in one portion of the damper device and is in contact with the hydraulic fluid. In the event of a defect or a leak in the damper device the part of the door closer that is associated with resisting spring must therefore also be opened. The high repair cost that is incurred by this procedure generally results closer in the necessity of complete replacement of the door closer.
In DE 198 20 382 A1 a door closer is described that exhibits an energy storage [i.e., reservoir] in the form of a resisting spring that is present but separated from the closer shaft via a pulling means. A damper device is not provided for in this type of door closer.
DE 195 482 02 A1 shows a friction damper for that type of door closer that must be provided separately in a guide rail of the closer assembly. Such a friction damper does not achieve the desired closing process that can be obtained using hydraulic damper/attenuation element.
It is therefore the purpose of the present invention to create a door closer that has a streamlined construction. In addition, the present invention seeks to create a door closer in which the drive assembly and the damping assembly can be separated from one another in a simple manner.
These tasks are solved by the door closer having the characteristics set forth in this application and the related claims.
Because the resisting spring and the closer shaft are not in contact with the fluid of the damper device they are not affected by the dynamic pressure occurring with the operation of the damper device. The resisting spring and the closer shaft can therefore be arranged in a relatively simple configuration, particularly in housings that are not fluid-tight that are furthermore of a thin-walled execution. Because of this there is a material and labor cost advantage at the time of manufacture. Furthermore, the minimal wall thickness of the housing in the area of the energy storage reduces the overall dimension and the weight of the door closer.
If the energy storage, the closer shaft, and the damper device are consolidated in a common structural unit the housing sections can be adapted to the individual requirements of the components with respect to their design and the thickness of their walls. They can, however, be mounted together on the door or on the frame as is done in a conventional door closer. The resisting spring can operate via a driver, especially by way of a chain on the closer shaft. This provides a simple, economical, and reliable transmission of power.
Depending on the installation situation it may be advantageous if the damper device is arranged in a radial direction next to the closer shaft or if the damper device is set up in the axial direction to the closer shaft. Likewise it can sometimes be advantageous if the closer shaft is situated between the resisting spring and the damper device. On the other hand the arrangement of the damper device and the energy storage on the same side of the closer shaft may be beneficial. The closer shaft is then located as far as possible to the end of the housing.
It is a further advantage if the damping/attenuation device includes a damper piston that is driven by a rod, for example, by a linkage. In this case the damping/attenuation device and the resisting spring can be arranged parallel, especially coaxially, in their effective direction. The forces [i.e., moments] acting on the closer shaft can be effectively balanced. Satisfactory kinematics and flat construction of the door closer, particularly in the axial direction, is possible if the closer shaft can be rotated around an axis that is placed essentially perpendicular.
Particular benefits are obtained if the damping/attenuation device is arranged with its separate housing section so as to rotate around the resultant direction. Depending on the installation setting the damping/attenuation device with its adjustment valves can then be so oriented such that they can be adjusted from an accessible side of the doorframe or the door panel. The housing section surrounding the damping/attenuation device in the direction of the closer shaft can carry an annular running collar facing outward, which catches the open groove towards the shaft and with it forms a rotational bearing. It is beneficial if the resisting spring is a helical spring that is externally encased in a sleeve, whereby the end of the sleeve facing the closer shaft forms an inward connection that is formed as a counter bearing/end stop for the resisting spring. Furthermore, the initial torque (pre-stressing) of the resisting spring can be adjusted by way of an adjusting device acting on the end of the sleeve opposite to the closer shaft. In this manner a simple and operationally reliable adjustment contrivance is provided.
If the pulling means at least segmentally opposes the jacket surface of the covering of the closer shaft, then the jacket surface preferably exhibits a angular-dependent varying distance from the middle axis of the closer shaft. The effective lever or balance arm, with which the drivers is engaged at the closer shaft, can be almost freely adjusted. It is therefore advantageous if the effective lever arm of the drivers is coarsest at the closer shaft in the area of low door opening angle. This can be achieved particularly effectively in that the drivers engages the closer shaft in the area of low door opening angle via a lever, so that a somewhat cosinusoidal torque is achieved, the drivers abuts the closer shaft at a greater opening angle, so that the moment [i.e., inertia] from that point does not essentially further diminish.
A good comfort level on opening the door in the area of medium door opening angle is provided if the effective lever arm of the drivers at the closer shaft in the area of medium door opening angle. In addition the effective lever arm can increase to an excessively large door opening angles. When this happens an increase of the opening power in the case of an opened door is attained. Although this condition does not kinematically limit the door opening angle it nonetheless prevents the door, at constant force, from striking against an obstacle.
When doing so the variation of the lever or balance arm can be ascertained quite easily by way of the thickness and/or form of the drivers, particularly concerning the different lengths of links of a drive chain. There are multiple possible variations are that are overall inexpensively accessible.
In the following a design example of the present invention is described in detail referring to the drawings.